Adsorbing evaporative emission during fueling of automotive vehicles

ABSTRACT

Fuel vapors which are normally lost in fueling automotive vehicles and from fuel storage tanks are adsorbed on an adsorbent, preferably activated carbon, and are subsequently recovered therefrom.

U ted States Patent 1 1 1111 3,748,829 Joyce et al. July 31, 1973 1 1ADSORBING EVAPORATIVE EMISSION [56] References Cited DURING FUELING 0FAUTOMOTIVE UNITED STATES PATENTS HF W n in 2,154,072 4 1939 Kamrath220/86 x [75] Inventors: Ronald Stone Joyce, Pittsburgh, 2,675,0934/1954 McCall et al. 55/387 X George Robert Stonebumer, 3,289,71112/1966 Hall 220/86 x coraopolis, both of Pa 3,581,782 6/1971 Onufer141/59 [73] Assignee: Calgon Corporation, Pittsburgh,-

p Primary Examiner-Robert L. Lindsay, Jr. Filed: Ju y 0 Attorney-WilliamL. Kreyer and Herbert J. Zeh, Jr.

[ 1 pp N04 51,964 57 ABSTRACT Fuel vapors which are normally lost infueling automo- 52] C 55/ 55/3 /5 tive vehicles and from fuel storagetanks are adsorbed 0/86 R on an adsorbent, preferably activated carbon,and are [51] Int. Cl Bold 53/14 subsequently recovered therefrom. [58]Field of Search 210/446, 448, 449;

55/316, 387, 389, DlG. 30, 74; 220/86 R, 85 F; 123/136; 141/59 2 Claims,6 Drawing Figures ADSORBING EVAPORATIVE EMISSION DURING FUELING OFAUTOMOTIVE VEHICLES BACKGROUND OF THE INVENTION The present inventionrelates to the adsorption and recovery of fuel vapors.

The problem of evaporative loss of volatile fuel for automotive vehiclesis one of growing significance to the petroleum and automotiveindustries. The smog and pollution problem created by such evaporativelosses is at least as important as the economic loss of valuablegasoline or the like.

No satisfactory method has been found or adopted to control the loss offuel by evaporation during fueling of automobiles, from normal breathingin filling station storage tanks, or by transferring gasoline eitherfrom tank trucks to filling stations or from the refineries to tanktrucks.

Assuming a distillation range for a typical gasoline stated as follows:

Percent Evaporated F Initial Boiling Point 90 I I25 50 215 90 335 EndPoint 415 the amount of evaporative loss on a hot summer day duringtransfer of gasoline from a filling station pump to an automobile may beestimated at 0.25 percent. Even on a cold day, i.e., 32F., evaporativeloss could amount to a significant percent, depending on the turbulenceand exposure to an outlet which is permitted.

Such evaporation represents a pollution and health problem, and adangerous, combustible or explosive atmosphere which is all too common,particularly in urban areas.

SUMMARY OF THE INVENTION We have invented a device and system for thecontrol of evaporative emissions from hydrocarbon fuels, particularlygasoline.

Our invention includes the use of an adsorbent device to adsorb fuelvapors in combination with the nozzle or other means for delivering fuelto a tank such as an underground storage tank or an automobile tank. Ina preferred embodiment, the device is disposed in such a way on thedelivery means that escaping vapors must pass through the adsorbent. Thepreferred adsorbents are activated carbons but there can be employedother hydrocarbon vapor adsorbents, such as molecular sieves. As typicalof the activated carbon adsorbents suitable for the invention mention ismade of Pittsburgh Activated Carbon-type BPX activated carbon (8 X 20United States Sieve Series) and Pittsburgh Activated Carbon-type BPL" l2X 30 United States Sieve Series).

The invention will be understood best in connection with the drawingswherein:

FIG. 1 is a broken away view partially in section of one embodiment ofthe invention;

FIG. 2 is a sectional view along the line 22 of FIG. 1;

FIG. 3 is a broken away view partially in section of another embodimentof the invention;

FIG. 4 is a view partially broken away of an alternative embodiment;

FIG. 5 is a partial sectional view of still another form of theinvention;

FIG. 6 is a perspective view of an alternative form of the invention;and

Referring more specifically to FIGS. 1 and 2 of the invention, when itis desired to refuel an automobile with gasoline, there is inserted intothe upper end of the automobiles fuel tank (3) a gasoline pump hosenozzle (4). A generally cylindrical canister (8) having outer wall (10)surrounds nozzle (4). The canister is filled with activated carbonparticles (14) and is in tight engagement with the circular end of fueltank (3) so that as vapors leave the fuel tank (3) they are forced to gothrough the activated carbon particles in the canister (8) by way ofinlet ports (17). The activated carbon adsorbs any gasoline vapors whichcome out of the gasoline tank during the filling operation whilepermitting the air which is being displaced from the fuel tank duringthe filling to pass out into the atmosphere through ports (16), locatedon the top of the canister (8).

In the modification shown in FIG. 3 there is attached to the pump (24) acanister (18) filled with activated carbon particles (20). An auxiliaryhose (22) connects the canister (18) with a sealed chamber (25)surrounding the gasoline filling hose (4). Gasoline vapors from the tank(3) pass directly into chamber (25). As a result, all of the gasolinevapors pass via hose (22) to canister (18) where they are adsorbed bythe activated carbon while the air being displaced from the gasolinetank passes through the canister into the atmosphere.

Canister 18) can be of considerably larger capacity than canister (8)since it need not be attached to the movable hose.

Whenever the canisters (8) and (18) have reached a desired level ofadsorption they can be removed and regenerated by heating, preferablywith steam distillation, to recover the gasoline volatiles.

As shown in FIG. 4 the canister containing activated carbon can bemounted on the frame (34) of the automobile. The auxiliary hose (36)which is permanently attached to sealed chamber (25) connects thecanister (30) with the chamber (25) surrounding the gasoline fillinghose (4) while the automobile is receiving gasoline.

In FIG. 5, a scheme is shown to minimize the loss of vapors andevaporative emissions from filling station storage tanks, both by normalbreathing and during filling. Gasoline storage tank (40) is locatedunderground and is fitted with a breather pipe (42) extending at leastto the ground surface. As shown, the breather pipe (42) normallyprojects to a considerable height. At its top, it is fitted withcanister (46) having a cover (43) which has holes (45) in its side forescaping air and unadsorbed vapors. The canister (46) has a bottomsupport (48) defining a chamber for holding activated carbon (44) and achamber (49) for distributing the vapors and gas over the entire bottomsurface of the upper chamber Bottom support (48) contains holes (47)which permit the entrance of vapors and gas while holding the carbon inplace.

As shown in FIG. 6, during filling of the storage tank (not shown)through supply inlet (51) from gasoline delivery truck the gasoline isdelivered via hose (52). As the underground storage tank fills, the airand gasoline vapors which are replaced pass through a separate outlet(53) and hose (56) to canister (58) on the truck. The canister is filledwith activated carbon (60) and is open to the atmosphere or is exited tothe truck tank (50). There is no air pollution since the gasoline vaporsare adsorbed by the activated carbon. When the carbon is exhausted, itcan be regenerated and the adsorbed gasoline recovered. The canisterwith spent carbon can then be returned to the refinery to recover theadsorbed carbon, e.g., by steam distillation. Alternatively, the spentcarbon can be reactivated by attaching it to the fuel vapor recoverysystem of the gasoline delivery truck and permitting air to sweep theadsorbed gasoline out of the canister and into the delivery trucksengine manifold.

Although it is normally uneconomical to attempt'to recover and use thevolatiles from a single canister such as shown in FIG. 1, the system isquite useful for pollution control even if the saturated carbon isdiscarded. However, a number of such canisters, or the carbon thereincan be regenerated and the vapors economically reclaimed by an airpurge, or simply regenerated by a steam purge.

We claim:

1. Method of preventing the escape of gasoline vapor into the atmosphereduring the transfer of gasoline from a storage container through agasoline pump hose into an automotive fuel tank comprising placing acylindrical canister having openings in each end thereof and filled witha gasoline vapor adsorbent material around the hose nozzle and in tightengagement therewith and in tight engagement with the opening of theautomotive fuel tank so that the vapors leaving the fuel tank are forcedthrough the canister.

2. Method as in claim 1 wherein the gasoline vapor adsorbent material isactivated carbon.

2. Method as in claim 1 wherein the gasoline vapor adsorbent material isactivated carbon.